Theftproof roadlight mounting



N. A. 'roRNBLoM E1- m. 2,202,472

THBF'IQPROOF ROADLIGHT OUNTING- May 28, 1940.

Filed llarch 30, 1939 \WH .Z

Patented May 28, 1940 I' Nils A. Tornblom, Chicago, and Irwin4 Meyer,

Cicero, Ill., assignors to Appleton Electric Company, a corporation ofllllinois v VApplication March `30, l19.39, SeriallNo.` .264,912 I 6 clams. (Cl. 24S- 203) It is common practice to mount lamps on the front bumpers of automobiles for road illumination purposes. As the fittings for holding such lamps in place are'now constructed, it is a comparatively easy matter for unauthorized persons f to detach the lamps and take them away.

The object of the present invention 'is toproduce a simple and novel construction for mounting a lamp on an automobile bumper or other part upon which it may be desired to clamp a lamp support, which will make it very dini-'cultto detach a lamp and thus make it'reasonably certain that lamps of this type will not be stolen.v n

The various features of Anovelty whereby vour invention is characterized will hereinafterbe pointed out with particularity in the claims; but. for a full understanding of our invention and of its objects and advantages, referencemaybe had to the following detailed description taken. in`

2th connection with the accompanying drawing,

Figure 1v -is a rear-elevation of one of the iniproved mountings for a lamp, including the saddle member of the lamp proper; Fig. 2 is aview,

partly inside elevation and partly in section, of the structure shown in Fig.`1, afragment of ther lamp housing being shown in dotted lines; Fig. 3

is a sectional View of that portion of the xture on which the lamp base rests, on the same plane as that in which the section is taken'in Fig. 2,. with the bolt and the sleeve nut shown in elevation instead of in section and Fig. 4 is a section taken on line 4--4 of Fig. 2.

Referring Ito the drawing, I `ande2 representl` clamping jaws adapted to be placed respectively` on top of and underneathV a wbar member of an,

automobile bumperand to be secured together so as to clamp the bar between them. r Resting uponV the member SI is one end of an arm 3 for sup.-v

-porting a lamp. The members I and 3 preferably have circular faces in engagement with each other, these faces being serrated, as .indicated at'4; in order to permit the arm to be adjusted into various angular positions uponthe clamping member. A single .bolt 5 serves to connect together the members I, 2 and 3; this bolt passing down through the members I and 3 at the center ofthe circular contact faces between these two members, and having'on its upper end a hea'dii,` that rests on top of the arm. On the lower end of the bolt, below the member 2, is a nut 1. After the device has been applied to a bumper baror other similar member, it remains fixed to the latter as long as the nut is tight. In order to detach the fixture, the nut need only be un` screwed.r One .of the features of our invention fhas to" do with guarding against runauthorized unscrewing of this'nut. Tothis end a recess y8 that is fairly deep and of a diameter considerably greater than the longest transverse dimension of the `nut I'is provided in the under side of ythe clamping jaw 2, this recess being coaxial A sturdy, cup-shaped cap 9j large enough in diameter to' receive the nut 'I' and deep enough so that it will standclear of with the bolt hole.

both the nut vin .the lower end of the bolt, has

its open end inserted in the recess 8, after theI nut has been tightened. This cap has aperipheral annular groove IIJ close enough to thefrim offthecupsoas to lie wholly in the recess when the cap is in place. II are drilledv radially of the axis ofthe recess through the annular wall bounding' the recess; the diameter of these holes beingy approximately the'samc as the width of thegroove III. 'After the fixture has been fastened to the bumper and the cap has been inserted in the recess 8. pins I2 are driven into the holes II these pins being sufficiently short so` thatthey-will not project be-v yond theouter faces of the` clamping member `when they are Afully entered in the annular groove inthe cap. Consequently, after these pins have?.

been driven in;.they cannot be removed except by a workman' provided withfa drill with which to destroy them by drilling. Obviously, no ordinary. sneak thief could remove these pins and. thus gaine access to the nut 'I to unscrew'the same. K' 'l It is not suiiicient merely. to make the. fixture theft-proof, but it should also Vbe impossible to detach the lamp from the fixture without damaging Ithe lamp; at least to the extent of making lit 'necessary to break the "lens,

e Another" feature of our invention has todo with a connection between the lamp and theV arm 3, which shall meet these requirements. In the arrangement shown,

the free end of the 'arm 3 has a hemispherical part `I4 on the upper side, this part fitting into a socket I5 in the under side'ofaJ- base member I6 forming part of a saddle I I- which serves to support the lamp fcasing indicated at A. A bolt I8 is screwed up through the base mem'ber I6 at the center of the vsocket and'may be locked against rotation by means of a jam nut I9 on the upper y end. 'I'he free end'of the arm 3 is substantially an inverted cup of which the spherical .part I4 forms the bottom. A large hole 20 is formed inv the center ofthe bottom wall `of this -cup to per'- mit the saddle to rock lin any direction. The

lower end of the bolt I8vis inthe form of a 'ball' which may be flattened inthat area that formsr 15 Any desired number of holes f v the end face of the bolt. Surrounding the ball 2| is a sleeve nut 22 which has a bore that is cylindrical for some distance inwardly from' one end and then becomes semi-spherical; a hole 24 being out to the other end of the nut from the bottom of the spherical seat in the nut, for the passage of the stem portion of the bolt. The hole 24 is somewhat larger in diameter than the body porA tion of thebolt and, with the hole 20, may form a chamber :or bore in the form of an inverted frustum of a cone.

It will be seen that the sleeve nut must be placed on the bolt before the bolt is screwed into the lamp base, since the sleeve nut cannot be removed from the headed end of the bolt. It will also be seen, as best shown in Fig. 3, that whereas the screw threads 25 on the bolt are righthand threads, the threads 26 on the sleeve nut are lefthand. Obviously, in assembling the parts, the bolt must be slipped up through the sleeve nut after the latter has been screwed into the supporting arm, and be screwed into and through the lampl base by means of a suitable tool.

The parts may initially be assembled in such a manner that the lamp cannot thereafter be shiftedl on its supporting arm. or bracket; or, if the sleeve nut is notv initially screwed in as far as it will go, the connection may at any time be loosened sumciently to permit the lamp to be adjusted angularly at any time. However, after an assembly has once been made, the lamp cannotbe detached by a mere unscrewing operation. Thus, even if the friction between the sleeve nut and the ball-like head of the bolt were `suflicient to cause a turning of the bolt in the event that a wrench could be applied to the sleeve nut, the bolt would not unscrew but would be caused to turn in a direction to screw it more tightly into the lamp base. Consequently, any effort tending to unscrew the sleeve nut, simply draws it -against the head of the bolt and, if anything, tends to screw the bolt in more tightly; thus making it impossible for the lamp to be detached by an ordinary sneak thief.. Even should itrbe possible to open the lamp casing so asto gain access to the nut i9, removal of this nut can be prevented by securing the nut to the boltr with a pin 2l drivenl in as are the pins i2.

U The fact that thebolt cannot be unscrewed by unscrewing the sleeve nut makes it possible to tighten the connection between the lamp and the supporting arm by simply applying to the sleeve nut a force in the direction tending to unscrew the same, since that serves to draw the sleeve nut rtightly against the head of the bolt and afterwards to turn the bolt in a direction to make the ft still tighter. l

While we have illustrated and described with particularity only a single' preferred form of our invention, we do not desire to be limited to theexact structural details thus illustrated and described; but intend to cover' all forms and arrangements which come within the definitions of our invention constituting the appended claims.

We claim:

1. In combination, two members having complementary surfaces in the form of sections of a sphere in engagement wit'h each other, one of said members having a bore of large diameter extending into the same from the side opposite said surfaces, a sleeve nut screwed into said bore, a bolt extending radially of the aforesaid surfaces through the interior of said nut and screwed at one end into the second of said members, said bolt having a head at the other end, and said nut having a portion of the bore therethrough in the form of a socket fitting the under side of the bolt head, the threads on the bolt and on the nut being oppcsitely handed.

2. In combination, two members having complementary surfaces in the form of sections of a sphere in engagement with each other, one of said members having a bore of large diameter extending into the same from the side opposite said surfaces, a sleeve nut screwed into said bore, a bolt extending radially of the aforesaid ysurfaces through the interior of said nut and screwed at one end into the second of said members, said bolt having a ball-shaped head at the other end, and said nut having a portion of the bore therethrough in the form of a socket fitting the undery side of the bolt head, the threads on the bolt and-on the nut being oppositely handed.

3. In combination, two members havingA complementary surfaces-in the form of sections of a sphere in engagement with each other, one of said members having a bore of large diameter extending into-the same from the side opposite said surfaces, a sleeve nut screwed into said bore, a bolt extending radially of the aforesaid surfaces through the interior of said nut and screwed at one end into the second of said me-mbers, said bolt having a ball-shaped head at the other end, and said n'ut having a portion of the` bore therethroughl inthe form of a socket ting the under side of the bolt head, the threads on the bolt and on the nut-being oppositely handed, that portion of the bore `'in the sleeve nut around the body of the bolt being larger` than the bolt topermit the bolt andthe member into which itis screwed to be shifted angularly uponthe other member.

4. In combination, a lamp base member andan underlying supporting member having complementary surfaces in the` form ofsections of a sphere in engagement with each other, the supporting member having aV bore of Alarge diameter extending upwardly into the same from the under side toward saidsurfaoes, a sleeve nut screwed into said bore, a boltextending radially of the aforesaid surfaces through the interior Vof said nut and screwedat one end into the lamp base membeig said bolt having a head at the lower end, and said nut having a portion of the bore therethrough in the form of a socket fitting the upwardly-facing side of the bolt head.

5. In combination, a lamp base member and an underlying supporting member having complementary surfaces in the form of sections of a sphere in engagement with each other, the supporting member having a bore of large diameter extending into the same from lthe under side, a sleeve nut screwed into said bore, a bolt' extending radially of the aforesaid surfaces through the interior of said nut and screwed at one end into thelamp base member, said bolt having a ball-shaped head at the lower end, and said nut having a portion of the bore therethrough in the form of a socket fitting the upwardly-facing side of theV bolt head, the threads on the bolt and on the nut being oppositely handed.

6. In combination, a lamp-base member and an underlying supporting member having com` plementary surfaces in the form of sections of a sphere in engagement with each other, the sup-` porting member having a borerof large diameterA extending into the sameirom the underside, a sleeve nut screwed into said bore, a bolt extending radially of lthe aforesaid surfaces through the interior of said nut and screwed at the upper end into the lamp base membensaid boli',` having arball-shaped head at the lower end, said nut having aportion of the bore therethrough in the form of a socket fitting the upwardly-facing side of the bolt head, the threads l onthe boltand on lthe nut! `being oppositely handed, and `that portion of' the bore in the ,sleeve nut around 'the' body of lthe bolt being larger than the boli; to permit the boit` and the lamp `loasemember to be shifted in unison angu- 5 y `larly upon' the other'member. Y' 'y ,v l

NILs A. TORNBLOM. 

